Strip-shaped high temperature superconductors (HTSC) typically include a metal substrate and an HTSC layer. The HTSC layer is a cuprate superconductor, mainly of a rare earth/barium/copper oxide compound (e.g., yttrium barium copper oxide (YBCO)). A pair of high temperature superconductors may be combined to form a neutral fiber conductor. To form a neutral fiber conductor, a thin metallic cover layer (called a cap) is applied onto each high temperature superconductor strip (and specifically, on the HTSC layer). Subsequently, the two metallic cover layers are soldered together. The combined metallic cover layers not only render the HTSC layer passive, but also act as an adhesion promoting primer.
Additional metal layers (e.g. copper) may be electroplated onto the metallic cover layer. In operation, the metallic cover layer must be applied to the HTSC layer prior to electroplating the metal layer. Otherwise, the HTSC layer would take part in the electro-chemical reaction, reducing its current-carrying ability. Since metallic cover layers are prepared utilizing physical methods such as sputtering (requiring the method to be performed under vacuum), these processes require a high outlay of apparatus, which is expensive.
Thus, it would be desirable to provide a process for producing HTSC strips having a cover layer that avoids the above-described problems.